1. Field of the Invention:
The present invention relates generally to ventilation on ships and, more particularly, to ventilation systems for the interior portion of ocean going ships having several decks.
2. Description of the Prior Art:
Generally, ships with several decks and several areas lying one behind the other in the longitudinal direction of the ship, separated by bulkheads, use a central ventilation system, preferably which includes at least one air delivery ventilator, one recirculation ventilator, one air heater and one air cooler. Generally, there is also an air conditioning apparatus, to give the air inside the ship a certain humidity, for example. On military ships, there is generally also an ABC (atomic, biological, chemical) filter set located ahead of the air delivery ventilator which prevents the penetration of radioactively-contaminated air inside the ship. A typical ventilation system for a ship is described in U.S. Pat. No. 4,428,318, issued Jan. 31, 1984, entitled "Ventilation Arrangement For A Cargo Ship", which patent is incorporated by reference as if the entire contents thereof were fully set forth herein.
Although the central ventilation system is located between two bulkheads at a central point of the ship, the ventilated spaces are distributed throughout the ship between various bulkheads. Therefore, on ships of the prior art, it is inevitable that air ducts in the longitudinal direction of the ship must be laid through the bulkheads. But this has the serious disadvantage, especially on a warship, since the hot gases can rapidly spread throughout the entire ship through the inflow and exhaust ducts, such as, in the case of a fire caused by combat damage. Of course, attempts have been made to confront this problem by installing heavy safety valves in the inflow and exhaust ducts in the area of the bulkheads, but such measures are relatively expensive, and the danger exists that in case of a fire, the closing mechanism on the safety valves may fail or the ventilator valves located in the area in question may no longer be accessible, so that in spite of their presence, the spread of the fire inside the ship through the ventilation system could not easily be prevented.